Alkaline liquid hard-surface cleaning compositions, including those which contain hard water sequestrants, are well known. The alkalinity provides improved grease cleaning properties but often necessitates the use of sequestrants. In alkaline compositions, divalent cations, e.g., Mg.sup.++, Ca.sup.++, react with carbonates and other anionic species in hard water and form solid precipitates. These precipitates can form on hard surfaces thus appearing as a visible film, or within alkaline concentrates when diluted with hard tap water prior to use. Sequestrants (e.g., phosphates, EDTA, polycarboxylates) are incorporated into alkaline hard-surface cleaning compositions to help prevent formation of these insoluble salts. The sequestrants bind to the hard water cations to thus prevent the formation of insoluble hard water precipitates.
Acidic liquid, hard-surface cleaning and disinfecting compositions are also well known. These compositions are commonly used to clean and disinfect hard bathroom surfaces. Unlike alkaline compositions, these acidic compositions can contain quaternary ammonium disinfectants. Quaternary ammonium disinfectants are not typically compatible with hard water sequestrants in alkaline compositions. Acidic compositions do not require a sequestrant since divalent hard water cations do not readily form solid precipitates in acidic environments, e.g., there are insufficient amounts of anionic species in the acidic compositions to react with the divalent cations to form solid precipitates. Without sequestrants in the compositions, quaternary ammonium disinfectants can be more easily incorporated into the acidic hard-surface cleaning compositions. However, the quaternary ammonium disinfectant contributes to filming and streaking, and acidic compositions are less effective than alkaline compositions in cleaning greasy dirt.
Given the forgoing, there is a need to provide a stable, alkaline liquid hard-surface cleaning composition which contains both a quaternary ammonium disinfectant and a sequestrant. It is therefore an object of the present invention to provide such a composition. It is a further object to provide such a composition which also does not cause filming or streaking on hard surfaces.